A media environment that tilts to the right is obscuring what President Obama stands for and closing off political options that should be part of the public discussion.

Yes, you read that correctly: If you doubt that there is a conservative inclination in the media, consider which arguments you hear regularly and which you don't. When Rush Limbaugh sneezes or Newt Gingrich tweets, their views ricochet from the Internet to cable television and into the traditional media. It is remarkable how successful they are in setting what passes for the news agenda.

The power of the Limbaugh-Gingrich axis means that Obama is regularly cast as somewhere on the far left end of a truncated political spectrum. He's the guy who nominates a "racist" to the Supreme Court (though Gingrich retreated from the word yesterday), wants to weaken America's defenses against terrorism and is proposing a massive government takeover of the private economy. Steve Forbes, writing for his magazine, recently went so far as to compare Obama's economic policies to those of Juan Peron's Argentina.

Democrats are complicit in building up Gingrich and Limbaugh as the main spokesmen for the Republican Party, since Obama polls so much better than either of them. But the media play an independent role by regularly treating far-right views as mainstream positions and by largely ignoring critiques of Obama that come from elected officials on the left.

This was brought home at this week's annual conference of the Campaign for America's Future, a progressive group that supports Obama but worries about how close his economic advisers are to Wall Street, how long our troops will have to stay in Afghanistan and how much he will be willing to compromise to secure health-care reform.

In other words, they see Obama not as the parody created by the far right but as he actually is: a politician with progressive values but moderate instincts who has hewed to the middle of the road in dealing with the economic crisis, health care, Guantanamo and the war in Afghanistan.

While the right wing's rants get wall-to-wall airtime, you almost never hear from the sort of progressive members of Congress who were on an America's Future panel on Tuesday. Reps. Jared Polis of Colorado, Donna Edwards of Maryland and Raul Grijalva of Arizona all said warm things about the president -- they are Democrats, after all -- but also took issue with some of his policies.

All three, for example, are passionately opposed to his military approach to Afghanistan and want a serious debate over the implications of Obama's strategy. "If we don't ask these questions now," said Edwards, "we'll ask these questions 10 years from now -- I guarantee it."

Polis spoke of how Lyndon Johnson's extraordinary progressive legacy "will always be overshadowed by Vietnam" and said that progressives who were challenging the administration's foreign policy were simply trying to "protect and enhance President Obama's legacy by preventing Afghanistan and Iraq from becoming another Vietnam."

As it happens, I am closer than the progressive trio is to Obama's view on Afghanistan. But why are their voices muffled when they raise legitimate concerns, while Limbaugh's rants get amplified? Isn't Afghanistan a more important issue to debate than a single comment by Judge Sonia Sotomayor about the relative wisdom of Latinas?

Polis, Edwards and Grijalva also noted that proposals for a Canadian-style single-payer health-care system, which they support, have fallen off the political radar. Polis urged his activist audience to accept that reality for now and focus its energy on making sure that a government insurance option, known in policy circles as the "public plan," is part of the menu of choices offered by a reformed health-care system.

But Edwards noted that if the public plan, already a compromise from single-payer, is defined as the left's position in the health-care debate, the entire discussion gets skewed to the right. This makes it far more likely that any public option included in a final bill will be a pale version of the original idea.

Her point has broader application. For all the talk of a media love affair with Obama, there is a deep and largely unconscious conservative bias in the media's discussion of policy. The range of acceptable opinion runs from the moderate left to the far right and cuts off more vigorous progressive perspectives.

Democrats love to think that Limbaugh and Gingrich are weakening the conservative side. But guess what? By dragging the media to the right, Rush and Newt are winning.